The present invention relates to a semiconductor device with protective means against overheating, and more particularly to a semiconductor device which has means for protecting the circuit section of the device from overheating due to the excessive temperature rise of the semiconductor elements provided within the circuit section.
In a semiconductor device comprising a circuit section having active elements, the junctions of these elements generate heat as the device operates. When the temperature of the junctions rises above a particular value, the circuit section will be broken down. A semiconductor device is known which is designed to protect itself from overheating. In this device, a heat-sensitive element such as a heat-sensing transistor is formed on a semiconductor substrate, along with the active elements, and the output signals of the heat-sensitive element control the active elements.
In the semiconductor device, this active elements and the heat-sensitive element are formed on the same semiconductor substrate. It is therefore difficult to trim the substrate after forming these elements, such that the elements can have design precision. Also since the heat-sensitive elements are not electrically insulated from that portion of the substrate which surrounds the heat-sensitive element, parasitic actions will occur inevitably between the active elements.